Outgoing House Majority Leader Eric Cantor’s Virginia congressional district hatched a minor revolution to bump the conservative congressman for someone more adamantly conservative. Yet a perception of inattentiveness to hometown needs was at least among the factors that took Cantor down.

Mississippi Sen. Thad Cochran got a scare by finishing second in his Republican primary amid a tea party uprising against the incumbent. But this week he received a runoff reprieve.

Later this summer, tea party passion will get a test in the Kansas primary.

Here, in a red state that’s turning ever more crimson in recent elections, establishment conservative Pat Roberts seeks re-election to the U.S. Senate against a distant cousin of the president’s, painting the three-term incumbent as typical of what’s wrong with Washington.

Their Aug. 5 Republican primary might test not only how angry Kansas Republicans have grown with the feds, but also whether tea party activism holds any more surprises. Milton Wolf, whose family tree crosses with that of President Barack Obama, carries the tea party flag along with money from national groups in an upstart challenge to politics as usual.

“We’ll probably have a better idea in a week,” said Clay Barker, the executive director of the Kansas Republican Party. “You’ll see how people react to the Cochran race, whether that discourages the tea party people or makes them angry and active.”

He and others say the outcome in Mississippi might douse the embers stoked in Cantor’s Virginia upset. Or the opposite. Politics is, after all, as much tea leaves as trigonometry. The expectation of a low turnout, and consequently less predictable primary, also throws uncertainty into any prognostication.

Yet Wolf’s odds remain long. A mid-June poll by SurveyUSA showed Roberts leading by 56-23 percent. Roberts’ campaign had raised $2.4 million through March, compared with the $556,000 Wolf collected. Independent expenditures, either from tea party forces for Wolf or mainstream Republican groups for Roberts, might still play a role.

On the ideological front, Roberts always approached politics from the right. He’s only veered further starboard lately. He’s locked up endorsements from virtually every other Republican politician in the state.

Wolf’s campaign got knocked off balance before the race began in earnest. In February, The Topeka Capital-Journal reported that Wolf, a wealthy radiologist, had posted unsettling images of dead patients in 2010 with seemingly callous commentary to Facebook: “What kind of gun blows somebody’s head completely off? I’ve got to get one of those.”

Shortly after that story broke, word circulated that a radiology firm in which Wolf is a partner faces charges of illegal price fixing in a civil suit. Wolf and his partners vehemently deny the charge.

Wolf has said he regrets the Facebook posts and long ago removed them, and he argues that the Roberts campaign incorrectly claims patients’ privacy was violated. There was nothing, Wolf’s campaign notes, in the posts that would violate federal privacy laws by revealing the identity of the people in the images.

Wolf would rather talk about how his insights as a physician would make him a powerful voice against the Affordable Care Act, known by critics as Obamacare. He also prefers to discuss how he sees Roberts as having become a creature of Washington.

On that last point, analysts say, Wolf may be most likely to gain traction. The son of a Republican national committeeman, Roberts dates his days in Washington to the late 1960s, when he was a congressional aide. He was elected from the most western and most rural Kansas congressional district in 1980 and has been a fixture on Capitol Hill ever since. He was elected to the U.S. Senate in 1996.

Wolf sees Roberts as a Virginia resident _ and unsuccessfully attempted to challenge his legal residency. The incumbent owns a home in Alexandria, Va., leases out his western Kansas home and uses a house in Dodge City in which he rents space from a donor for his voter registration.

“He’s been in Washington for 47 years,” Wolf is fond of saying. “He wants you to forget about the first 46.”

While Roberts can boast hard-right bona fides that play well in a Kansas Republican primary, he’s taken a subtle shift further in that direction in recent years.

His record fighting for agriculture subsidies might cut two ways. It engenders loyalty to farmers in the western part of the state, but much of the primary electorate comes from the Kansas City suburbs and Wichita. Their voters are often less enamored with federal agriculture spending.

In 1998, Roberts criticized “fringe” politicians and said his party didn’t win elections by “limiting our membership and our appeal to a narrow agenda.”

Two years ago, he was among those who voted against ratifying a United Nations treaty on rights for people with disabilities. Former Sen. Bob Dole, once the most powerful Kansan in modern times and a mentor to Roberts, was in the chamber for the vote. Roberts sided against Dole, a disabled veteran, in favor of the conservative cause of the moment: the perception that the treaty would surrender a measure of American sovereignty.

It’s that positioning that makes Wolf’s task tough.

“Roberts doesn’t look like the most vulnerable incumbent,” said Neal Allen, a political science assistant professor at Wichita State University. “He’s not . . . as oblivious to the threat as other Republican incumbents.”

In fact, Roberts’ campaign manager issued a memo to reporters this week bullet-pointed with reasons that Wolf can’t win.

“All that (Wolf) has done has made no difference in this race,” Leroy Towns, Roberts’ campaign manager, said in an interview.

To the Wolf camp, the memo reeked of electoral self-doubt.

“We do believe there’s a national trend and that we’ll feel the effect of it here in Kansas,” Wolf campaign manager Ben Hartman said.